SLDS190B November   2012  – March 2022 TFP401A-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information
    5. 6.5  DC Digital I/O Electrical Characteristics
    6. 6.6  DC Electrical Characteristics
    7. 6.7  AC Electrical Characteristics
    8. 6.8  Timing Requirements
    9. 6.9  Switching Characteristics
    10. 6.10 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 TMDS Pixel Data and Control Signal Encoding
      2. 7.3.2 TFP401A-Q1 Clocking and Data Synchronization
      3. 7.3.3 TFP401A-Q1 TMDS Input Levels and Input Impedance Matching
      4. 7.3.4 TFP401A-Q1 Device Incorporates HSYNC Jitter Immunity
    4. 7.4 Device Functional Modes
      1. 7.4.1 TFP401A-Q1 Modes of Operation
      2. 7.4.2 TFP401A-Q1 Output Driver Configurations
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Typical Application
        1. 8.1.1.1 Design Requirements
        2. 8.1.1.2 Detailed Design Procedure
          1. 8.1.1.2.1 Data and Control Signals
          2. 8.1.1.2.2 Configuration Options
          3. 8.1.1.2.3 Power Supplies Decoupling
        3. 8.1.1.3 Application Curves
        4. 8.1.1.4 DVDD
        5. 8.1.1.5 OVDD
        6. 8.1.1.6 AVDD
        7. 8.1.1.7 PVDD
    2. 8.2 Power Supply Recommendations
    3. 8.3 Layout
      1. 8.3.1 Layout Guidelines
        1. 8.3.1.1 Layer Stack
        2. 8.3.1.2 Routing High-Speed Differential Signal Traces (RxC-, RxC+, Rx0-, Rx0+, Rx1-, Rx1+, Rx2-, Rx2+)
      2. 8.3.2 Layout Example
      3. 8.3.3 TI PowerPAD 100-TQFP Package
  9. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Electrostatic Discharge Caution
    5. 9.5 Glossary
  10. 10Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.3.3 TFP401A-Q1 TMDS Input Levels and Input Impedance Matching

The TMDS inputs to the TFP401A-Q1 receiver have a fixed single-ended termination to AVDD. A laser trim process internally optimizes the TFP401A-Q1 device to fix the impedance precisely at 50 Ω. The device functions normally with or without a resistor on the EXT_RES pin, so it remains drop-in compatible with current sockets. The fixed impedance eliminates the need for an external resistor while providing optimum impedance matching to standard 50-Ω DVI cables.

Figure 7-1 shows a conceptual schematic of a DVI transmitter and TFP401A-Q1 receiver connection. A transmitter drives the twisted-pair cable through a current source, usually using an open-drain type of output driver. The internal resistor, matched to the cable impedance at the TFP401A-Q1 input, provides a pullup to AVDD. Naturally, with the transmitter disconnected and the TFP401A-Q1 DVI inputs left unconnected, the TFP401A-Q1 receiver inputs pull up to AVDD. Figure 7-2 shows the single-ended differential signal and full-differential signal. The design of the TFP401A-Q1 device is for response to differential signal swings ranging from 150 mV to 1.56 V, with common-mode voltages ranging from (AVDD – 300 mV) to (AVDD – 37 mV).

GUID-8B991553-59B4-4422-A53D-2AE652FE5C40-low.gifFigure 7-1 TMDS Differential Input and Transmitter Connection
GUID-1D4E0449-22FE-410E-8E1B-BB4F494C9EF4-low.gifFigure 7-2 TMDS Inputs